my_foods = ['pizza','falafel','carrot cake']
#没有索引是将两个变量名指向了同一个列表
friend_foods = my_foods
my_foods.append('cannoli')
friend_foods.append('ice cream')

print('My favorite foods are:')
print(my_foods)

print('\nMy friend\'s favorite foods are:')
print(friend_foods)
